The Bycan SK‑2440/U is a 40 A industrial battery charger used in high‑power aircraft and lift equipment, typically supplying 48 V DC to heavy‑duty batteries. Common failure modes for this class include failed rectifier diodes, overheating of the power MOSFET array, degraded heat sink mounting leading to thermal runaway, and failure of the internal temperature sensor causing false shutdowns. Initial checks should verify that the input AC supply is within spec and that the charger’s output voltage remains stable under load; inspect the PCB for burnt components or cracked solder joints, and confirm that the cooling fan and heat sink are clean and securely mounted before proceeding to component testing or replacement.[oss-gpt-20b]